Identifying one or more access points in one or more channels to facilitate communication

• US 7,616,604 B2
• Filed: 10/25/2005
• Issued: 11/10/2009
• Est. Priority Date: 10/25/2005
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Walker, Jennifer K., Abdelhamid, Hisham S., Toor, Kamaldip S., Guidorizzi de Siqueira, Marcio, Laux, Carlos V.
• Primary Examiner(s): Eng; George
• Assistant Examiner(s): Torres; Marcos L
• Application Number:
  US11/258,925
• Publication Number:
  US 20070091839A1
• Time in Patent Office: 1,477 Days
• Field of Search: 370/329, 370/328, 370/338, 455/418, 455/434, 455/446, 455450-453
• US Class Current: 370/329
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists
• CPC Class Codes: H04W 36/00837 Determination of triggering parameters for hand-off
• CPC Class Codes: H04W 36/0085 Hand-off measurements
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Identifying one or more access points in one or more channels to facilitate communication includes identifying an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network. The first channel band includes a plurality of channels and the first frequency range includes a plurality of channel bands. The identified access point is used to communicate with the network. A scanning sequence is initiated in the first frequency range and a second frequency range to identify one or more access points in one or more channels to facilitate communication. The second frequency range includes a plurality of channel bands.

Claims

1. A method for identifying one or more access points in one or more channels to facilitate communication, comprising:

identifying an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network, the first channel band comprising a plurality of channels and the first frequency range comprising a plurality of channel bands;

communicating with the network using the identified access point;

maintaining a plurality of priority lists comprising;

a first priority list comprising known channels of the first frequency range, the known channels previously identified by a node as being used by at least one access point;

a second priority list comprising unknown channels of the first frequency range, the unknown channels not previously identified by the node as being used by at least one access point;

a third priority list comprising channels of a second frequency range comprising a plurality of channel bands; and

initiating a scanning sequence to identify one or more access points in one or more channels to facilitate communication, the scanning sequence indicating how often to scan each priority list.

2. The method of claim 1, wherein initiating a scanning sequence comprises:

conducting maintenance scanning; and

conducting discovery scanning.

3. The method of claim 2, wherein conducting maintenance scanning comprises scanning one or more known channels in the first channel band of the first frequency range to identify the one or more access points.

4. The method of claim 2, wherein conducting discovery scanning comprises:

scanning one or more unknown channels in the first channel band of the first frequency range to identify the one or more access points;

scanning one or more channels of one or more second channel bands of the first frequency range to identify the one or more access points, each second channel band comprising a plurality of channels; and

scanning one or more channels of the first channel band and the one or more second channel bands of the second frequency range to identify the one or more access points.

5. The method of claim 1, further comprising updating a channel list to include the one or more channels corresponding to access points identified during the scanning sequence.

6. The method of claim 1, wherein initiating a scanning sequence comprises initiating a scanning sequence according to a priority list, wherein initiating a scanning sequence according to a priority list comprises:

conducting maintenance scanning to identify one or more access points in one or more known channels in a first channel band of the first frequency range;

conducting discovery scanning to identify one or more access points in one or more unknown channels in the first channel band of the first frequency range; and

conducting discovery scanning to identify one or more access points in one or more channels in one or more second channel bands of the first frequency range.

7. The method of claim 6, wherein initiating a scanning sequence according to a priority list comprises:

conducting discovery scanning to identify one or more access points in one or more channels in the first channel band or the one or more second channel bands of the second frequency range.

8. Logic for identifying one or more access points in one or more channels to facilitate communication, the logic embodied in a data storage medium and operable to:

identify an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network, the first channel band comprising a plurality of channels and the first frequency range comprising a plurality of channel bands;

communicate with the network using the identified access point;

maintain a plurality of priority lists comprising;

a first priority list comprising known channels of the first frequency range, the known channels previously identified by a node as being used by at least one access point;

a second priority list comprising unknown channels of the first frequency range, the unknown channels not previously identified by the node as being used by at least one access point;

a third priority list comprising channels of a second frequency range comprising a plurality of channel bands; and

initiate a scanning sequence to identify one or more access points in one or more channels to facilitate communication, the scanning sequence indicating how often to scan each priority list.

9. The logic of claim 8, wherein initiating a scanning sequence comprises:

conducting maintenance scanning; and

conducting discovery scanning.

10. The logic of claim 9, wherein conducting maintenance scanning comprises scanning one or more known channels in the first channel band of the first frequency range to identify the one or more access points.

11. The logic of claim 9, wherein conducting discovery scanning comprises:

scanning one or more unknown channels in the first channel band of the first frequency range to identify the one or more access points;

scanning one or more channels of one or more second channel bands of the first frequency range to identify the one or more access points, each second channel band comprising a plurality of channels; and

scanning one or more channels of the first channel band and the one or more second channel bands of the second frequency range to identify the one or more access points.

12. The logic of claim 8, the logic further operable to update a channel list to include the one or more channels corresponding to access points identified during the scanning sequence.

13. The logic of claim 8, wherein initiating a scanning sequence comprises initiating a scanning sequence according to a priority list, wherein initiating a scanning sequence according to a priority list comprises:

conducting maintenance scanning to identify one or more access points in one or more known channels in a first channel band of the first frequency range;

conducting discovery scanning to identify one or more access points in one or more unknown channels in the first channel band of the first frequency range; and

conducting discovery scanning to identify one or more access points in one or more channels in one or more second channel bands of the first frequency range.

14. The logic of claim 13, wherein initiating a scanning sequence according to a priority list comprises:

conducting discovery scanning to identify one or more access points in one or more channels in the first channel band or the one or more second channel bands of the second frequency range.

15. A system for identifying one or more access points in one or more channels to facilitate communication, comprising:

one or more access points operable to facilitate communication with a network; and

a node operable to;

identify an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network, the first channel band comprising a plurality of channels and the first frequency range comprising a plurality of channel bands;

communicate with the network using the identified access point;

maintain a plurality of priority lists comprising;

a first priority list comprising known channels of the first frequency range, the known channels previously identified by a node as being used by at least one access point;

a second priority list comprising unknown channels of the first frequency range, the unknown channels not previously identified by the node as being used by at least one access point;

a third priority list comprising channels of a second frequency range comprising a plurality of channel bands; and

initiate a scanning sequence to identify one or more access points in one or more channels to facilitate communication, the scanning sequence indicating how often to scan each priority list.

16. The system of claim 15, the node further operable to:

conduct maintenance scanning; and

conduct discovery scanning.

17. The system of claim 16, the node further operable to scan one or more known channels in the first channel band of the first frequency range to identify the one or more access points.

18. The system of claim 16, the node further operable to:

scan one or more unknown channels in the first channel band of the first frequency range to identify the one or more access points;

scan one or more channels of one or more second channel bands of the first frequency range to identify the one or more access points, each second channel band comprising a plurality of channels; and

scan one or more channels of the first channel band and the one or more second channel bands of the second frequency range to identify the one or more access points.

19. The system of claim 15, the node further operable to update a channel list to include the one or more channels corresponding to access points identified during the scanning sequence.

20. The system of claim 15, the node further operable to initiate a scanning sequence according to a priority list comprising:

conducting maintenance scanning to identify one or more access points in one or more known channels in a first channel band of the first frequency range;

conducting discovery scanning to identify one or more access points in one or more unknown channels in the first channel band of the first frequency range; and

conducting discovery scanning to identify one or more access points in one or more channels in one or more second channel bands of the first frequency range.

21. The system of claim 20, the node further operable to initiate a scanning sequence according to a priority list comprising:

conducting discovery scanning to identify one or more access points in one or more channels in the first channel band or the one or more second channel bands of the second frequency range.

22. A node for identifying one or more access points in one or more channels to facilitate communication, comprising:

an interface operable to communicate with a plurality of access points of a network; and

a scanning engine operable to;

identify an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network, the first channel band comprising a plurality of channels and the first frequency range comprising a plurality of channel bands;

communicate with the network using the identified access point;

maintain a plurality of priority lists comprising;

a first priority list comprising known channels of the first frequency range, the known channels previously identified by a node as being used by at least one access point;

a second priority list comprising unknown channels of the first frequency range, the unknown channels not previously identified by the node as being used by at least one access point;

a third priority list comprising channels of a second frequency range comprising a plurality of channel bands; and

initiate a scanning sequence to identify one or more access points in one or more channels to facilitate communication, the scanning sequence indicating how often to scan each priority list.

23. The node of claim 22, the scanning engine further operable to:

conduct maintenance scanning; and

conduct discovery scanning.

24. The node of claim 23, the scanning engine further operable to scan one or more known channels in the first channel band of the first frequency range to identify the one or more access points.

25. The node of claim 23, the scanning engine further operable to:

scan one or more unknown channels in the first channel band of the first frequency range to identify the one or more access points;

scan one or more channels of one or more second channel bands of the first frequency range to identify the one or more access points, each second channel band comprising a plurality of channels; and

scan one or more channels of the first channel band and the one or more second channel bands of the second frequency range to identify the one or more access points.

26. The node of claim 22, the scanning engine further operable to update a channel list to include the one or more channels corresponding to access points identified during the scanning sequence.

27. The node of claim 22, the scanning engine further operable to initiate a scanning sequence according to a priority list comprising:

conducting maintenance scanning to identify one or more access points in one or more known channels in a first channel band of the first frequency range;

conducting discovery scanning to identify one or more access points in one or more unknown channels in the first channel band of the first frequency range; and

conducting discovery scanning to identify one or more access points in one or more channels in one or more second channel bands of the first frequency range.

28. The node of claim 27, the scanning engine further operable to initiate a scanning sequence according to a priority list comprising:

conducting discovery scanning to identify one or more access points in one or more channels in the first channel band or the one or more second channel bands of the second frequency range.

29. A system for identifying one or more access points in one or more channels to facilitate communication, comprising:

means for identifying an access point in a channel in a first channel band of a first frequency range to facilitate communication with a network, the first channel band comprising a plurality of channels and the first frequency range comprising a plurality of channel bands;

means for communicating with the network using the identified access point;

means for maintaining a plurality of priority lists comprising;

a first priority list comprising known channels of the first frequency range, the known channels previously identified by a node as being used by at least one access point;

a second priority list comprising unknown channels of the first frequency range, the unknown channels not previously identified by the node as being used by at least one access point;

a third priority list comprising channels of a second frequency range comprising a plurality of channel bands; and

means for initiating a scanning sequence to identify one or more access points in one or more channels to facilitate communication, the scanning sequence indicating how often to scan each priority list.